Double-beat valve



Man". 2%), 11923.

D. COCKBURN ET AL DOUBLE BEAT VALVE Filed Sept. l2, 1921 Patented Mar, 2th, 1923.,

UNETEE) DAVID GOCKBURN AND DONALD MACNICOLL, OF CAB/DONALD, NEAR GLASGOW, SCOTLAND.

DOUBLE-BEAT VALVE.

Application filed September 12, 1921. Serial No. 500,145.

T all whom it may concern:

Be it known that we, DAVID CooKnUnN and DONALD MAoNIooLL, subjects of the King of the United Kingdom of Great Britain and Ireland, and residing at Clydesdale Engineering Works, Cardonald, near Glas gow, Scotland, have invented a certain new and useful Improvement in Double-Beat Valves, of which the following is a specification.

This invention relates to double beat valves of thetype equipped with a flexible diaphragm for permitting both valve elements to seat notwithstanding differences in expansion between the valve proper and the valve casing.

Valves of this type as constructed heretofore are associated with a diaphragm fitted to one of the valve elements. I

The present invention consists broadly in a double beat valve in which the flexible diaphragm is interposed between the valve casing and the bottom valve seat so that said valve seat is capable of slight movement relatively to the valve casing.

A secondary feature consists in the provi-- sion of means for holding said seat rigidly in position when the operative face is to be ground in, such means comprising a spaced series of pinching screws fitted to the bottom cover of the valve and adjustable to force the valve seat into a position such that a rigid shoulder thereon engages a corresponding shoulder on the valve casing.

Yet a further feature consists in the fitment on the valve spindle of a protective curtain which surrounds the spindle surface passing through the stufiing box and thereby prevents the flow of superheated steam on. to

said surface.

The invention is illustrated in the accompanying drawing in which Fig. 1 is a fragmentary section of a valve and Fig. 2 a detail sectional view drawn to a larger scale.

The double beat valve shown is provided with a flexible diaphragm 1 interposed between the valve casing 2 and the bottom valve seat 3 so that the valve seat 3 is capable of slight movement relatively to the valve casing 52. The outer marginal edge of the diaphragm 1 is nipped between the valve casing 2 and a junk ring ,4. and the inner marglnal edge is nipped between a nut 5 and a collar 6 on the seat 53. the complemental faces of the collar (3 and the junk ring f being shaped to permit the requisite flexure of the diaphragm. The nut 5 is held against rotation by locking screws 7.

For holding the seat 3 rigidly in. position. when the operative face is to be ground in there is fitted to the bottom cover 8 a spaced series of pinching screws 9 which are adjustable into engagement with the lower edge of the valve seat 3 to force the valve seat 3 into a position such that a rigid shoulder 10 on the collar 6 engages a corresponding shoulder 11 on the valve casing.

Fitted on the valve spindle 12 is a pro tective curtain 13 surrounding the spindle surface which passes through the stuffin box 14. The curtain 13 arrests the flow of superheated steam towards the spindle surface and prevents the formation of a hard deposit thereon.

We claim 1. In combination with a valve casing having upper and lower valve seats, a double beat valve for said seats. and a diaphragm interposed between said casing and said lower valve seat, permitting slight movement of said lower valve seat relatively to said casing.

2. In combination with a valve casing resenting a shoulder, upper and lower valve seats, said lower seat also presenting a shoulder, a doubel beat valve for said seats, a diaphragm interposed between said casing and said. lower valve seat, permitting normally slight movement of said lower valve seat relatively to said casing a bottom cover, and a spaced series of pinching screws fitted to said cover and adjustable to force said lower seat into a position with said shoul ders in engagement with one another.

3. In combination with a valve casing having upper and lower valve seats, a valve spindle, a double beat valve on said spindle, a stuffing box for said spindle, a diaphragm interposed between said casing and said lower valve seat, permitting slight movement of said lower valve seat relatively to said casing, and a protective curtain fitted to said spindle surrounding the spindle suriace which passes @through vsaid stnfling In testimony whereof we have signed our DAVID COCKBURN. DONALD MAONICOLL.

Witnesses KATE FOTHERINGHAM, ISABEL RoLLo. 

